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81.
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83.

Purpose

To investigate the effectiveness of displacement of submacular hemorrhage (SMH) caused by polypoidal choroidal vasculopathy (PCV) by assessing retinal sensitivity using microperimetry.

Methods

We retrospectively reviewed the medical records of 11 consecutive PCV patients with SMH. All patients underwent vitrectomy, subretinal injection of tissue plasminogen activator, and fluid-air exchange, followed by antivascular endothelial growth factor therapy using a pro re nata regimen. The retinal sensitivity was measured by use of microperimetry before and after surgery.

Results

The mean (SD) age of the patients was 74.1 ± 9.4 years. The mean SMH diameter was 6.8 ± 5.2 disc diameters. The best-corrected visual acuity (BCVA), mean retinal sensitivity, and mean number of measure points with a sensitivity ≥10 dB before the surgery were 0.94 ± 0.49, 4.2 ± 4.5 dB, and 15.6 ± 15.1 points, respectively. These had significantly improved 6 months after surgery (0.39 ± 0.37, 15.6 ± 7.3 dB, and 50.9 ± 22.2 points, respectively; P < 0.05 for all outcome measures). The mean number of measure points with an absolute scotoma before surgery had decreased significantly 6 months after surgery (from 40.5 ± 15.0 to 9.4 ± 16.0 points; P < 0.001).

Conclusions

Displacement of SMH effectively improves retinal sensitivity as well as BCVA.
  相似文献   
84.
Porphyromonas gingivalis is a gram-negative anaerobic bacterial species implicated as an important pathogen in the development of adult periodontitis. Hemagglutinin may mediate the adsorption and invasion of bacteria into host cells. Furthermore, the hemagglutinin plays a role in the agglutinate and lyse erythrocytes intake of heme which is an absolute requirement for this bacterial growth. We previously cloned the gene encoding the 130-kDa hemagglutinin protein domain (130-kDa HMGD) and identified the functional motifs of agglutination of erythrocytes. Bacterial cell attachment to erythrocytes is an important initial step in the expression of hemolytic activity. In this study, we highly purified recombinant r130-kDa HMGD and prepared the specific antiserum. Further, the effect of the antibody on the hemolytic activity of P. gingivalis cells was examined. The polyclonal antibody recognized 43,49-kDa major bands in P. gingivalis cells and r130-kDa HMGD, and significantly inhibited the hemagglutinating and hemolytic activities of P. gingivalis cells. The findings suggest that the antibody may be useful in the development of the passive immunization against periodontal diseases caused by P. gingivalis infection.  相似文献   
85.
86.
Journal of Natural Medicines - Brazilian propolis (AF-08) is a dietary supplement containing a variety of flavonoids. It is used worldwide as a folk medicine. Flavonoids and a diet of fruits and...  相似文献   
87.
Our laboratory previously reported the usefulness as biomarkers of exosomes in the plasma of esophageal squamous cell carcinoma (ESCC) patients. However, the influence of tumor‐derived exosomes on the tumor itself and underlying mechanisms remain unclear. We here report changes in the phenotype and gene expression when cancer cells exist in an environment with tumor‐derived exosomes. The exosomes were isolated from the culture medium of human ESCC cells (TE2, T.Tn) by ultracentrifugation; cell proliferation assay, wound‐healing assay, and fluorescence imaging of the cell cycle were performed to clarify the phenotypic changes in the high concentration of tumor‐derived exosomes. Gene expression changes were also assessed by mRNA microarray, and the data were analyzed by gene set enrichment analysis (GSEA). The data revealed that the proliferation of both TE2 and T.Tn was inhibited, and cell migration ability was upregulated in the exosome exposure group (P < .05). Fluorescence imaging using a fluorescent ubiquitination‐based cell cycle indicator expressing ESCC cells revealed that the ratio of G1‐phase cells was significantly increased in the exosome exposure group (P < .05). Findings of the GSEA clarified that high‐density exposure of cancer‐derived exosomes to their parent cancer cells downregulated the expression of genes related to cell proliferation and cell cycle, and upregulated the expression of genes related to actin filament length and extracellular structure organization. In conclusion, an environment of high‐density tumor‐derived exosomes induces changes in the gene expression and phenotype of tumor cells and may lead to tumor progression or malignant transformation.  相似文献   
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89.
The growth and differentiation of mast cells and melanocytes require stem cell factor (SCF), the ligand for the kit receptor tyrosine kinase. SCF may exist as a membrane-bound or soluble molecule. Abnormalities of the SCF-kit signaling pathway, with increased local concentrations of soluble SCF, have been implicated in the pathogenesis of the human disease cutaneous mastocytosis, but have not yet been shown to play a causal role. To investigate both the potential of SCF to cause mastocytosis and its role in epidermal melanocyte homeostasis, we targeted the expression of SCF to epidermal keratinocytes in mice with two different transgenes controlled by the human keratin 14 promoter. The transgenes contained cDNAs that either produced SCF, which can exist in both membrane-bound and soluble forms, or SCF, which remains essentially membrane bound. Murine epidermal keratinocyte expression of membrane-bound/ soluble SCF reproduced the phenotype of human cutaneous mastocytosis, with dermal mast cell infiltrates and epidermal hyperpigmentation, and caused the maintenance of a population of melanocytes in the interadnexal epidermis, an area where melanocytes and melanin are found in human skin but where they are not typically found in murine skin. Expression of membrane-bound SCF alone resulted in epidermal melanocytosis and melanin production, but did not by itself cause mastocytosis. We conclude, first, that a phenotype matching that of human mastocytosis can be produced in mice by keratinocyte overproduction of soluble SCF, suggesting a potential cause of this disease. Second, we conclude that keratinocyte expression of membrane-bound SCF results in the postnatal maintenance of epidermal melanocytes in mice. Since the resulting animals have skin that more closely approximates human skin than do normal mice, their study may be more relevant to human melanocyte biology than the study of skin of normal mice.  相似文献   
90.

Background

Proximal gastrectomy has been introduced for early gastric cancer located in the upper third of the stomach, but expansion of its indication to advanced tumors has not been generally accepted in terms of lesser curvature lymph node dissection.

Methods

We reviewed the medical records of 385 patients with tumors in the upper third of the stomach, and the incidence of metastasis and the therapeutic index related to the proximal (no. 3a) and distal (no. 3b) lymph nodes of the lesser curvature were analyzed and compared with those of tumors in the middle third (n = 1093) and lower third (n = 922) of the stomach.

Results

The no. 3a rate of metastasis from advanced tumors in the upper third of the stomach was significantly higher than that from tumors in the middle third or lower third of the stomach. The no. 3b metastasis rate did not show any significant differences between the three locations, but the therapeutic index of no. 3b lymph nodes in the upper third of the stomach (1.7) was far lower than that in the middle third (7.1) or lower third (7.0). Further, the rate of metastasis from tumors with the distal border ending in the upper third of the stomach (2.2 %) was significantly (P < 0.0001) lower than that from tumors located in the upper third of the stomach but extending to the middle third (19.6 %), as well as from tumors located in middle third (17.1 %) or lower third (19.6 %), with the therapeutic index being only 1.1. The four no.-3b-positive tumors all measured more than 40 mm, and included one T3 tumor and three T4 tumors.

Conclusion

Proximal gastrectomy with exclusion of no. 3b lymphadenectomy could be indicated for at least T2 tumors measuring less than 40 mm localized in the upper third of the stomach.
  相似文献   
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